1. Field of the Invention.
The present invention is related to a central annunciator and dynamic supervision system for smoke detection, and more particularly to a system for hotels, motels and apartment houses that will alert the area involved and a central location to an alarm and that is continually self-testing.
2. Description of the Prior Art.
In recent years, the development of low cost, efficient smoke detectors has provided reliable and economical protection of homes, rooms and offices. However, in multiple room structures such as motels, hotels, office buildings and the like, individual smoke detectors are of less value since rooms may not be occupied and a fire may be well under way before it is detected. There is therefore a need in such structures for central annunciation of conditions indicating the presence of smoke or other products of combustion.
Individual smoke detectors have been used having auxiliary switch contacts wired to a central annunciator. This type has proven relatively expensive since the units are not in mass production. In addition, the contact wiring does not provide means for supervision to ensure that all units are operating properly. It is also desirable to provide central power for all units to obviate the individual battery problem. Typical attempts in the prior art include U.S. Pat. No. 3,587,095 to Earling who shows a complex ac powered system having large numbers of electrical relays which may present reliability problems. Kabat teaches, in U.S. Pat. No. 4,017,852, connection of a number of smoke detectors together such that actuation of one alarm causes all alarms to sound. However, no means for indicating the location of the smoke or fire is provided.